GBS 8200/8220 CFW Project

[rama]

I wouldn't bother with shielding anymore. That problem was entirely the software.
It will still be beneficial to install more / better caps in some locations, mainly the 3 electrolytics around the main IC.
Also, the RGB potentiometers can be bypassed / removed, if you want to do that.

The most important hardware thing is using a sync stripper with some attenuation.

[AndehX]

Right, well my gscartsw has a sync stripper I can enable/disable. Everything seems to be working great, except the screen seems to periodically flicker, as if its briefly losing sync, and there's a distinct wobble to the image.

[rama]

Can't say much without knowing what exactly you get. I'm currently working on the SP and IF though, both could cause the sync issue.

For the wobble, that's probably the H-PLL. Try "s5s17s06j" and / or "t5t11t5", see if that does anything.
The H-PLL loop filter seems to behave a little different on each board. I don't know yet how to handle this best.

Also, there is a nice preset for NTSC on "9" that mimics plain line doubling. It works really well here.

[AndehX]

ok well most of what you said there went right over my head, since im just getting back into this. I'll try and get a video of the flickering in a bit. The wobble isnt actually that bad (I had it hooked up to my projector before, now its connected to a monitor and it looks fine)

[AndehX]

heres a video of the flickering. It seems to happen at somewhat regular intervals.

https://www.dropbox.com/s/xclbersegbepz ... 2.mp4?dl=0

[rama]

Yep, that's the clamp circuit. Console is a PSX or SNES?

[AndehX]

No, SNES is fine, no flickering at all. The video was recorded from my Gamecube

[rama]

Please post 5 lines of the output of the "i" command (info mode).

Edit:
Also try the latest update. I'm having some trouble with the docs probably having some bit meanings swapped.

[AndehX]

Yeah I updated and everything seems fine now. Here's a pic of my ghetto setup complete with bodged power switch



and heres a pic of the output on my projector:

[AndehX]

I noticed you added ESP32 support. I assume this was done for the extra memory?

[rama]

And ESP8266
It's for the wireless interfaces, meant to solve the user input problem.

The 32 is seriously fast though. It might be possible to sample the ADC clock with it, or otherwise help automatically deciding sampling time and phase.

[AndehX]

Good stuff. They're like £6 on a aliexpress too. I went ahead and ordered one last night

[shingouki2]

Hey guys fantastic work, I wanted to ask a few questions. Does the arduino code need to be modified before uploading or does it just work out of the box?

Also with the new firmware, is the component in being stretched? Cause by default component in isn't stretched and is in a little window.

[rama]

The presets try to fill the screen, no matter if RGBS or YpPbPr.

You don't have to change anything in the Arduino sketch.
If you want to use one of the new devices, just select one from the Arduino IDE boards list and compile.

[shingouki2]

Does component out have to be set?

[AndehX]

There seems to be alot of horizontal glitching and flashing green lines with 480i sources in the latest updates

[rama]

Possibly, yes. That would depend on your sync setup. Specifically, how it differs from mine.
I've enabled SP retiming mode, which requires SP phase to be correct. The method by which I do this isn't great.
Try "t5t57t6" to turn it off, or try "886" a few times, see if it goes away.

I'm in a pretty big WiP stage right now.

shingouki2:
Yes, and it requires a hardware modification as well if you want it to look nice (replacing one resistor).
I don't have a preset for it right now. Simply not enough manpower :p

[rama]

AndehX:
What console has the dropouts and how do you have it connected (sync)?
I did a test with my PS2, using RGBS and Component inputs. Both methods work very well with an interlaced game, at 50 and at 60Hz.
PS2 is pretty much nailed, it looks like!

[AndehX]

PS2 and Gamecube, I dunno, when I first switch them on, I get weird green lines flickering randomly. After a while it seems to settle down and looks ok though. Sync is just from my Gscartsw with the LM1881 switched on.

heres a video https://www.dropbox.com/s/k40b3h5owsug1 ... 9.mp4?dl=0

[rama]

I've never seen those green lines happen here.
When it works, it looks like you're trying to show something?
If you mean the deinterlace quality (or lack thereof), that's the best it'll get for now :p

Some PS2 games also look absolutely terrible with their interlacing.
They're trying to cover up the flicker but it ends up looking much worse on an HD display.
So far I haven't found a deinterlace option that doesn't require a second field buffer.
Once the basics are done though, this can be added as an option.
Quality should be much better then, at the cost of 16ms (ntsc) / 20ms (pal) more lag.

[AndehX]

yeah don't worry about the deinterlacing, that doesn't bother me. I was actually trying to catch the random horizontal flicker that seems to happen (or not in this case)

But yeah, that green shit happens, and seems to go away after I switch profiles a couple times...

[rama]

Remember to look in the sketch what profile you're loading, by the way.
"2" is for PAL, "9" is the same for NTSC. Yes, I'm assigning these randomly as I go along :p

Things will get labels once the UI is ready.

[Red_Delta]

So I'm having a bit of an issue that I can't seem to figure out myself. I was running old code, can't remember the exact date but it was when pins 4 and 5 were the only ones needed to run the software, and everything was working. I then updated to the latest software and I can't seem to get anything working. I have everything hooked up to the correct pins (Pin A4: SDA, Pin A5: SCL, Pin 10: VSYNC) butt I still do not get a signal. I only have a sega saturn to test with and am using a high quality scart cable from retroaccess that runs to a sync strike, which is in turn attached to my gbs-8200. I soldered to vsync alternative 3 and am using a arduino nano. Any ideas guys?

[shingouki2]

Whelp my board turned funny. I guess plugging A0 on the R pin did something. It's stuck in pink and it looks like the video processor is damaged. I get white/green sparkles now. It won't even reset. Also for above, I can vouch. Putting the board in programming mode with the jumper killed video out.

[AndehX]

Im getting weird vertical areas of green and weird glitches when I switch mine on. I usually have to switch it off and on a couple of times before the signal comes through right. I have a spare LM1881, so im going to try adding it to the GBS, instead of relying on the sync stripper in my gscartsw.

[falz]

Im getting weird vertical areas of green and weird glitches when I switch mine on.

I've always had something similar happen since I started using it months ago. My version is months old however and has forked a bit. My lines aren't green, but instead wavy pixels. 2 arduino reboots always seems to fix it. dunno.

[rama]

shingouki2:
Please watch your terminology if you're not entirely sure what's going on. Other people will read your comment, see the words "killed video out" and that's how rumors start.
What actually happens in quite expected:
Enabling the onboard MCU programming mode disables its operation. That's why we do it, to stop it interfering.
But without configuration from the Arduino or similar, there won't be any output. The Arduino has to work.

For the pink video, I don't think it happened from having the Arduino A0 connected to the GBS R line.
A0 is always either an input (to the ADC) or high-z, in case the Arduino is resetting.

I get white/green sparkles now. It won't even reset.

Does it work if you remove the Arduino and the programming jumper? (Ie: Revert the board to stock.)
You will have to experiment with your sync stripper or some different consoles, as the default software is utterly incapable of syncing to video signals.

[rama]

@falz:
Does it look like in this pic?
https://www.dropbox.com/sh/wjatft758hoe ... 202006.jpg

[falz]

Yeah very similar, although my lines seemed vertical and pixels would move/scroll up and down in vertical lines. i'll try to get a photo tonight.

[AndehX]

Right, so I installed my own LM1881 circuit and it seems to work good. I'm not getting those large green areas anymore, although I seem to be getting weird flickering interference, that goes away gradually after about 15-20 minutes. Heres a couple of images of my board:





Heres a video of the interference:

https://www.dropbox.com/s/n82k47qazmp1n ... 4.mp4?dl=0